Abstract: An apparatus includes a casing defining a fluid flow channel, the casing including one or more diaphragms each defining a portion of the fluid flow channel, a strain gauge disposed on one of the one or more diaphragms, the strain gauge having a characteristic responsive to a pressure of fluid in the fluid flow channel, a temperature-sensitive circuit element disposed on one of the one or more diaphragms, the temperature-sensitive circuit element having a characteristic responsive to a temperature of the fluid in the fluid flow channel, and temperature compensation circuitry electrically coupled to the strain gauge and to the temperature-sensitive circuit element.

Abstract: An apparatus includes a casing defining a fluid flow channel, the casing including one or more diaphragms each defining a portion of the fluid flow channel, a strain gauge disposed on one of the one or more diaphragms, the strain gauge having a characteristic responsive to a pressure of fluid in the fluid flow channel, a temperature-sensitive circuit element disposed on one of the one or more diaphragms, the temperature-sensitive circuit element having a characteristic responsive to a temperature of the fluid in the fluid flow channel, and temperature compensation circuitry electrically coupled to the strain gauge and to the temperature-sensitive circuit element.

Abstract: An amplifier circuit has a voltage input terminal, for receiving Vin, and a voltage output terminal, for outputting Vout. A feedback circuit controls Vout to match Vin. A differential input stage receives Vin and Vout and generates a first output signal. An output stage comprises a pull down circuit for Vout. A main MOSFET is controlled by the first output signal to pull down Vout to match Vin when Vout is above a threshold voltage Vtrans. An auxiliary MOSFET, in parallel with the main MOSFET, is controlled by the first output signal to pull down Vout to match Vin when Vout is below Vtrans. The main MOSFET is turned substantially off when Vout is below Vtrans. A headroom generator coupled between the Vout terminal and a drain of the auxiliary MOSFET allows the auxiliary MOSFET to operate in its active region and pull Vout to ground.

Abstract: A driver for an analog-to-digital converter (ADC) has an overall feedback loop between its input and its output for maintaining overall accuracy, and a much faster feedback loop in its output stage that quickly compensates for output transients before the overall feedback loop can substantially react to the transients. Output voltage transients are created by the intermittent capacitive load of the ADC. The fast feedback loop can be made very fast since there are only a few components in the fast feedback path. The fast reduction of the output transients enables a shorter sampling time, leading to more accurate analog-to-digital conversion. The overall gain of the driver can be set to be greater than unity while still providing good output transient suppression.

Abstract: A method of improving the slew rate of an amplifier is described where a differential pair of transistors receives a differential first control signal and second control signal. The tail current for the transistors is provided by a tail current regulator. The same control signals are applied to a slew boost controller, whose output increases as the differential between the control signals increase. The tail current regulator generates a bias signal that sets a minimum tail current. The tail current is controlled to be the minimum tail current until the slew boost output signal exceeds a threshold, whereupon the tail current increases in response to an increasing differential between the control signals. Common mode rejection is not adversely affected by the slew boost controller generating a slightly varying current under common mode conditions due to the minimum tail current.

Abstract: In a bipolar transistor, a thin gate oxide, preferably less than 600 ?, is formed over the base surface region between the emitter and collector. A conductive gate, such as doped polysilicon, is then formed over the gate oxide and biased at the emitter voltage. In the example of a PNP transistor, when the emitter is forward biased with respect to the base to turn the transistor on, the gate is at a positive potential relative to the base. This causes the holes in the base conducting the emitter-collector current to be repelled away from the surface, and the electrons in the base to be attracted to the surface, so that more of the emitter-collector current flows deeper into the base. Thus, the effect of defects at the base surface is mitigated, and 1/f noise is reduced. The invention is equally applicable to PNP and NPN transistors. Other benefits result.

Abstract: An amplifier circuit has a voltage input terminal, for receiving Vin, and a voltage output terminal, for outputting Vout. A feedback circuit controls Vout to match Vin. A differential input stage receives Vin and Vout and generates a first output signal. An output stage comprises a pull down circuit for Vout. A main MOSFET is controlled by the first output signal to pull down Vout to match Vin when Vout is above a threshold voltage Vtrans. An auxiliary MOSFET, in parallel with the main MOSFET, is controlled by the first output signal to pull down Vout to match Vin when Vout is below Vtrans. The main MOSFET is turned substantially off when Vout is below Vtrans. A headroom generator coupled between the Vout terminal and a drain of the auxiliary MOSFET allows the auxiliary MOSFET to operate in its active region and pull Vout to ground.

Abstract: A method of improving the slew rate of an amplifier is described where a differential pair of transistors receives a differential first control signal and second control signal. The tail current for the transistors is provided by a tail current regulator. The same control signals are applied to a slew boost controller, whose output increases as the differential between the control signals increase. The tail current regulator generates a bias signal that sets a minimum tail current. The tail current is controlled to be the minimum tail current until the slew boost output signal exceeds a threshold, whereupon the tail current increases in response to an increasing differential between the control signals. Common mode rejection is not adversely affected by the slew boost controller generating a slightly varying current under common mode conditions due to the minimum tail current.

Abstract: A driver for an analog-to-digital converter (ADC) has an overall feedback loop between its input and its output for maintaining overall accuracy, and a much faster feedback loop in its output stage that quickly compensates for output transients before the overall feedback loop can substantially react to the transients. Output voltage transients are created by the intermittent capacitive load of the ADC. The fast feedback loop can be made very fast since there are only a few components in the fast feedback path. The fast reduction of the output transients enables a shorter sampling time, leading to more accurate analog-to-digital conversion. The overall gain of the driver can be set to be greater than unity while still providing good output transient suppression.

Abstract: A method of fabricating an instrumentation amplifier to have an improved common mode rejection ratio (CMRR) vs. frequency initially trims resistors in the input amplifiers of the instrumentation amplifier during a DC test, where the inputs are shorted and a DC voltage is applied, so that the output of the amplifier is approximately zero. This will normally cause the transconductances of the two input amplifiers to be different. Thus, the AC CMRR will degrade with frequency. Trimmable capacitors are provided in the input section and are trimmed during a common mode AC test to cause the output voltage to be minimized during the AC test. This causes the two input amplifiers to have the same bandwidth and gm/C ratio.